Photographic processing compositions and processes using same

ABSTRACT

The shelf life of photographic developing compositions containing N-alkoxyalkyl substituted hydroxylamines is increased by addition of an oxyethylamino compound of the group consisting of triethanolamine, morpholine, N-ethylmorpholine, ethanol amine, 3-diethylamino-1,2-propanediol,N,N-diethylaminoethanol, tris-2propanolamine, N,N-dihydroxyethylglycine and cellulose diethylaminoethyl ether.

United States Patent l UN inventor Sidney Kasman Newton, Mass.

Appl. No. 725,145

Filed Apr. 29, I968 Patented Nov. 9, i971 Assignee Polaroid Corporation Cambridge, Mass.

PHOTOGRAPHIC PROCESSING COMPOSITIONS AND PROCESSES USING SAME 10 Claims, No Drawings U.S. Cl o. 96/29 R.

k 96/664 Int. Cl i. G03c 5/30, G030 5/54 Field oi Search 96/29, 76.

References C lted UNITED STATES PATENTS l0/i953 Robbins 96/663 3,337,342 8/1967 Green 96/29 3,345,l66 lO/l967 Land et al. 96/29 2,857,274 l0/I958 Land et al 96/29 2,857,274 ill/i958 Land et aim, 96/29 2,857,276 ill/i958 Land et al.... 96/29 3,287,125 ll/l966 Green et al. 96/29 3,293,034 l2/l966 Green et ul 96/29 Primary Examiner-William D. Martin ASJIXIUII! Examiner-Theodore G. Davis AImrneyr-Brown and Mikulka and Stanley H. Mervis PHOTOGRAPHIC PROCESSING COMPOSITIONS AND PROCESSES USING SAME This invention relates to photography and, more particularly, to photographic processing compositions having increased shelf life.

It is one object of this invention to provide novel photographic processing compositions having improved stability characteristics and particularly adapted for use in performing diffusion transfer processes.

Another object of this invention is to provide stabilizing agents for hydroxylamine silver halide developing agents.

The invention accordingly comprises the several steps and the relation and the order of one or more of such steps with respect to each of the others, and the compositions possessing the features, properties and the relation of elements which are exemplified in the following detailed disclosure, and the scope of the application of which will be indicated in the claims.

Other objects of this invention will in part be obvious and will in part appear hereinafter.

Hydroxylamines, particularly N-alkyl and N-alkoxyalkyl substituted hydroxylamines, have been proposed for use as silver halide developing agents in diffusion transfer processes. See, for example, U.S. Pats. No. 2,857,274, 2,857,275, 2,857,276. 3,287,124, 3,287,125 and 3,293,034. These hydroxylamine developing agents are especially useful in silver diffusion transfer processes where it is desired to be able to use the silver transfer image with little or no after treatment. Such diffusion transfer processes are performed at relatively high pH levels, and it is usually desirable to be able to store the highly alkaline hydroxylamine developing solution for long periods of time prior to use. Under such storage conditions, the hydroxylamine may undergo reactions, the precise nature of which is unknown but which result in a lowering of their photographic activity and effectiveness. If a polymeric thickening agent, e.g., hydroxyethyl cellulose, is present to impart viscosity to facilitate application of the processing solution, the polymer may be attacked as a consequence of these side reactions and the viscosity of the processing solution substantially reduced prior to use.

It has now been discovered that the shelf life of alkaline hydroxylamine developing solutions can be substantially improved by incorporating therein certain amines containing the oxyethylamino grouping The reason for the beneficial action of these oxyethylamino compounds is not known, but it is believed to be associated, at least in part, with their ability to act as free radical traps.

The photographic processing composition includes an alkali, preferably an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide; a silver halide solvent, such as an alkali metal thiosulfate, e.g.. sodium or potassium thiosulfate, or a cyclic imide of the type described in detail in the aforementioned U.S. Pats. No. 2,857,274, 2,857,275, 2,857,276, e.g., uracil, urazole, S-methyl-uracil, etc.; and the hydroxylamine silver halide developing agent. Particularly effective and preferred hydroxylamine developing agents may be described by the formula wherein R is alkyl, alkoxyalkyl or alkoxyalkoxyalkyl, and R is hydrogen, alkyl, alkoxyalkyl, alkoxyalkoxyalkyl or alkenyl. The alkyl, alkoxy and alkenyl radicals preferably contain from one to three carbons. Particularly useful hydroxylamine developing agents include N,N-diethyl-hydroxylamine, N,N- bis-methoxyethyl-hydroxylamine and N,N-bis-ethoxyethylhydroxylamine. Hydroxyethyl cellulose is particularly useful as a polymeric film-forming. thickening or viscosity-providing agent when the processing composition is intended to be applied by sprending in a thin layer between a photosensitive element and an image-receiving element in accordance with wellknown diffusion transfer processing techniques. The processing composition may also include conventional additives, such as antifoggants, toning agents, development accelerators, etc.-

The effectiveness of a particular oxyethylamino compound to improve the shelf life of a hydroxylamine processing composition may be readily determined by an accelerated aging test described below. The accelerated test results have been found to parallel more extended tests under milder conditions, eg storage for three weeks at 140 F. A processing composition containing an alkali metal hydroxide, an N-alkyl or N-alkoxyalkyl substituted hydroxylamine developing agent and the test oxyethylamino compound is prepared and used to fill rupturable pods of the type described in US. Pat. No. 3,056,49 l. The sealed pods are stored for 24 hours at C. The contents of the pods are analyzed by vapor phase chromatography to determine the percentage of hydroxylamine developing agent in the organic volatiles before and after storage for 24 hours at 85 C. The test processing compositions are so constituted that the only source of organic volatiles is hydroxylamine developing agent; an otherwise test processing composition containing no hydroxylamine developing agent yields no organic volatiles. As a result, the effectiveness of the oxyethylamino test compound is determined by comparing the difference or delta (A) between the percentage of hydroxylamine developing agent in the volatiles before and after the accelerated testing. The control processing composition is free of an oxyethylamino stabilizing agent. The higher the A, the greater was the loss of the hydroxylamine developing agent. I

An accelerated aging test of the above type was performed using the following processing composition as a control:

Potassium hydroxide I565 g. Uracil 80.0 g. Natrosol 2S0 (trade name of Hercules 50.0 g.

Corp. for hydroxyethyl cellulose.

high viscosity) Zinc acetate l5.0 g. N,N-bis-methoxyethyl-hydroxylumine 50.0 cc. Thiazolidine thione 0. l 5 g. Water l,000.0 cc.

The oxyethylamino compound being tested was added, for test purposes, in an amount equal to 5.6 g. per liter of the control processing composition. The results of this test are summarized below: I

In the absence of the oxyethylamino stabilizer, the viscosity of the stored pod was substantially reduced. The test compounds listed above contain the 1 I-0H,-0H,-0

grouping and substantially reduced the loss of the N,N-bismethoxyethyl-hydroxylamine. It will be recognized that the degree of effectiveness of any particular oxyethylamino compound may be affected by modifications in the composition of the processing composition. Such differences are ones of degree, however, and one skilled in the art may readily determine if a particular oxyethylamino compound is effective as a stabilizer and then modify a given hydroxylamine processing composition to take maximum advantage of the stabilizing action of that particular oxyethylamino compound.

The above tests clearly demonstrate the special effectiveness of triethanolamine and tris-Z-propanolamine and these are the preferred stabilizers of this invention, both from the standpoint of their stabilizing effectiveness and the fact that their presence made little, if any, difference in the sensitometric properties when the processing compositions were used to form silver transfer images in regenerated cellulose in accordance with the disclosure of the copending application of Edwin H. Land, Ser. No. 675,472 filed Oct. 16, 1967.

The concentration of the oxyethylamino stabilizing agent may vary considerably, depending upon the composition of the particular processing composition. In general, beneficial effects have been obtained using the oxyethylamino stabilizing agent in concentrations of from 1 to 80 g. per liter of processing composition, concentrations of about I to 30 g. per liter being preferred.

The aforementioned U.S. Pat. No. 2,857,274 proposed the use of a silver halide complexing system involving the combination of two complexing agents: a cyclic imide and a nitrogenous base. Numerous nitrogenous bases were disclosed, including some of those oxyethylamino compounds herein disclosed to be useful as stabilizing agents for hydroxylamine developing agents. The stabilizing action of the oxyethylamino compounds was unexpected and is limited to only a fraction of the compounds useful as nitrogenous bases in the procedures described in U.S. Pat. No. 2,857,274. In addition, it will be noted that this unexpected stabilizing action is evident using concentrations of the oxyethylamino compound much lower than would be used if the compound were being employed as the nitrogenous base in the aforementioned patent.

Since certain changes may be made in the above compositions and processes without departing from the scope of the invention herein involved, it is intended that all matter contained in the above description shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

l. A photographic developing composition comprising (a) an alkali metal hydroxide (b) a hydroxylamine silver halide developing agent of the formula wherein R is alkyl, alkoxyalkyl or alkoxyalkoxyalkyl and R is hydrogen, alkyl, alkoxyalkyl, alkoxyalkoxyalkyl or alkenyl, each of said alkyl, alkoxy and alkenyl groups containing from 4. A photographic developing composition as defined in claim 1, wherein said oxyethylamino compound is triethanolamine.

5. A photographic developing composition as defined in claim 1, wherein said oxyethylamino compound is tris-2- prcpanolamine.

. A photographic developing composition as defined in claim 1, wherein said hydroxylamine developing agent is N,N dimethoxyethyl-hydroxylamine.

7. A photographic developing composition as defined in claim 1, wherein said hydroxylamine developing agent is N ,N- diethoxyethyl-hydroxylamine.

8. A photographic developing composition as defined in claim 1 wherein said oxyethylamino compound is present in a concentration of about 1 to 30 grams per liter of said composition.

9. In a diffusion transfer process wherein an exposed silver halide emulsion is developed and an imagewise distribution of a diffusible silver complex is transferred to a regenerated cellulose silver receptive stratum to provide a silver transfer image, the step of performing said process using a photographic. developing composition comprising (a) an alkali metal hydroxide, (b) a hydroxylamine silver halide developing agent of the formula wherein R is alkyl, alkoxyalkyl or alkoxyalkoxyalkyl and R is hydrogen, alkyl, alkoxyalkyl, alkoxyalkoxyalkyl or alkenyl, each of said alkyl, alkoxy and alkenyl groups containing from one to three carbons, (c) a silver halide solvent and (d) an oxyethylamino compound selected from the group consisting of triethanolamine, morpholine, N-ethylmorpholine, ethanol amine, 3-diethylaminol ,2-propanediol, N ,N- diethylaminoethanol, tris-2-propanolamine, N,N-dihydroxyethylglycine and cellulose diethylaminoethyl ether, said oxyethylamino compound being present in a concentration effective to increase the shelf life of said composition.

10. A photographic developing composition as defined in claim I, wherein said silver halide solvent is uracil. 

2. A photographic developing composition as defined in claim 1, including a polymeric film-forming, viscosity-providing agent.
 3. A photographic developing composition as defined in claim 2, wherein said polymer is hydroxyethyl cellulose.
 4. A photographic developing composition as defined in claim 1, wherein said oxyethylamino compound is triethanolamine.
 5. A photographic developing composition as defined in claim 1, wherein said oxyethylamino compound is tris-2-propanolamine.
 6. A photographic developing composition as defined in claim 1, wherein said hydroxylamine developing agent is N,N-dimethoxyethyl-hydroxylamine.
 7. A photographic developing composition as defined in claim 1, wherein said hydroxylamine developing agent is N,N-diethoxyethyl-hydroxylamine.
 8. A photographic developing composition as defined in claim 1 wherein said oxyethylamino compound is present in a concentration of about 1 to 30 grams per liter of said composition.
 9. In a diffusion transfer process wherein an exposed silver halide emulsion is developed and an imagewise distribution of a diffusible silver complex is transferred to a regenerated cellulose silver receptive stratum to provide a silver transfer image, the step of performing said process using a photographic developing composition comprising (a) an alkali metal hydroxide, (b) a hydroxylamine silver halide developing agent of the formula wherein R1 is alkyl, alkoxyalkyl or alkoxyalkoxyalkyl and R2 is hydrogen, alkyl, alkoxyalkyl, alkoxyalkoxyalkyl or alkenyl, each of said alkyl, alkoxy and alkenyl groups containing from one to three carbons, (c) a silver halide solvent and (d) an oxyethylamino compound selected from the group consisting of triethanolamine, morpholine, N-ethylmorpholine, ethanol amine, 3-diethylamino-1,2-propanediol, N,N-diethylaminoethanol, tris-2-propanolamine, N,N-dihydroxyethylglycine and cellulose diethylaminoethyl ether, said oxyethylamino compound being present in a concentration effective to increase the shelf life of said composition.
 10. A photographic developing composition as defined in claim 1, wherein said silver halide solvent is uracil. 